#include <iostream>
#include <map>
using namespace std;


void print(map<string, int>& mp)
{
    for(auto x : mp) cout << x.first << " " << x.second << endl;
}
int main()
{
    map<string, int> mp;

    mp.insert({"张三", 10});
    mp.insert({"李四", 20});
    mp.insert({"王五", 30});

    // print(mp);

    // cout << mp["张三"] << endl;
    // if(mp["赵六"] == 0) cout << "赵六不存在" << endl;
    // else cout << "赵六存在" << endl;

    // cout << mp["赵六"] << endl;
    if(mp.count("赵六")) cout << "赵六存在" << endl;
    else cout << "赵六不存在" << endl;
    return 0;
}